Instant Pot Icelandic Yogurt AKA Skyr
Ingredients:
1 gallon nonfat/skim milk
¼ cup plain yogurt with live and active cultures
7 drops liquid animal rennet (single strength)
¼ cup cool unchlorinated water
1–2 tablespoons vanilla (optional)
½ cup sweetener i.e. pure maple syrup, honey, agave, etc. (optional)
Directions:
Add milk to a clean/sanitized pressure cooker pot.
Secure the lid and turn pressure release knob to a sealed position. Press the yogurt function button. Press adjust until display reads “boil”. For pressure cookers that don’t have the automatic boil function, simply use the slow cook or saute function to warm the milk to 190°F.
When boil cycle is complete (this takes about an hour), use a thermometer to check that the milk has reached 190°F. If it’s not to temperature, use the saute function to continue warming milk to 190°F.
Remove pot from cooker and place on top of a cooling rack. Stir milk occasionally, until it cools to 105°F (this takes about 2 hours). To hurry along the cooling process, put the pot in a sink full of ice water. This will cool it in 10-20 minutes. (note: I feel like the end product is smoother with the gradual cool down, but in a pinch, this works).
While milk cools, take the yogurt starter from the fridge and allow it to sit on the counter until ready to use.
When milk is 105°F, ladle 2-3 scoops into a bowl, add the yogurt starter and whisk until smooth. Pour back into the pot and whisk until well incorporated.
In a small bowl, combine ¼ cup of cool water and 7 drops of liquid animal rennet. Swirl to combine.
Pour water/rennet mixture into the pot of milk while whisking. Stir for at least 30 seconds to make sure the rennet is well incorporated.
Place pot back inside the base, secure the lid, press the yogurt function and adjust to incubate for 5 hours.
After 5 hours, the yogurt will be firm and there will be a definite border of whey around the outside edge of the yogurt. Cover and place the pot of yogurt in the fridge to chill, about 6 hours or overnight.
When chilled, spoon or scoop yogurt into 2 yogurt strainer bowls. Could also use 2 nut milk bags hung over a large bowl to collect the whey. Strain yogurt in the refrigerator for 1-2 hours (or even overnight) until it reaches desired thickness.
Pour yogurt into a bowl and add vanilla and sweetener, if using. Reserve whey for another use if desired.
Use an electric hand mixer to whisk until smooth, this can take about a minute depending on how thick it is. If a thinner yogurt is preferred, stir in some of the excess whey.
Store in a yogurt strainer bowl or in quart size Mason jars topped with white Mason jar lids. The yogurt will stay good in the fridge up to 2 weeks.
Serve cold topped with fruit, honey, jam, granola, chia seeds, nuts, etc, etc. The topping possibilities are endless!